[User-mode-linux-devel] Re: i modified uml-net-tools for 2.4.0-testX

[Mark-Andre H. <ho...@in...>]

Hi Jeff,

On 09:39 Tue, 26 Sep, Jeff Dike wrote:

> Sure.  Pretty it up and send it in.

 Okay, it's attached below. I tried to keep these changes very small,
which resulted in a rather stupid kludge. (I've marked it with comments.)

 UML with the debian 2.2 is running fine with 2.4.0-test7 as a host system
but not with -test8. Don't know what the trouble is.

> What's the tun device, anyway?  Is it something new or is it the 2.4 
> replacement for the tap device or something?

 It's a replacement for the old ethertap device which is replaced by
the `Universal TUN/TAP device driver support'.

 From the help page:

   When a program opens /dev/net/tun, the driver creates and registers a
   corresponding net device tunX or tapX. After the program closed above
   devices, the driver will automatically delete tunXX or tapXX device and 
   all routes corresponding to it.

  Bye,
    Mark


diff -ruP uml-net-tools/Makefile uml-net-tools.new/Makefile
--- uml-net-tools/Makefile	Mon Jul 24 20:45:32 2000
+++ uml-net-tools.new/Makefile	Tue Sep 26 16:10:59 2000
@@ -5,10 +5,13 @@
 all: um_eth_net_util um_eth_net_set
 
 um_eth_net_phy.o: um_eth_net_phy.c um_eth_net.h
-um_eth_net_tap.o: um_eth_net_tap.c um_eth_net.h
-um_eth_net_util.o: um_eth_net_util.c um_eth_net.h
+um_eth_net_tap.o: um_eth_net_tap.c um_eth_net.h config.h
+um_eth_net_util.o: um_eth_net_util.c um_eth_net.h config.h
 um_eth_net_set.o: um_eth_net_set.c um_eth_net.h
 
+config.h: makeconf.sh
+	sh makeconf.sh > config.h
+
 um_eth_net_util: $(UTIL_OBJS)
 	gcc $(CFLAGS) -o $@ $(UTIL_OBJS)
 
@@ -19,4 +22,4 @@
 	cd .. ; tar --exclude=CVS -zcf um_eth_net-0.005.tar.gz net/
 
 clean:
-	rm -rf um_eth_net_util um_eth_net_set *.o core *~
+	rm -rf um_eth_net_util um_eth_net_set config.h *.o core *~
diff -ruP uml-net-tools/makeconf.sh uml-net-tools.new/makeconf.sh
--- uml-net-tools/makeconf.sh	Thu Jan  1 01:00:00 1970
+++ uml-net-tools.new/makeconf.sh	Tue Sep 26 16:13:02 2000
@@ -0,0 +1,10 @@
+#!/bin/sh
+
+cat << EOF
+/* Generated automatically by makeconf.sh */
+
+EOF
+
+if test -f /usr/include/linux/if_tun.h ; then
+	echo "#define HAS_UNIVERSAL_TUNTAP 1"
+fi
diff -ruP uml-net-tools/um_eth_net.h uml-net-tools.new/um_eth_net.h
--- uml-net-tools/um_eth_net.h	Mon Jul 24 20:42:47 2000
+++ uml-net-tools.new/um_eth_net.h	Tue Sep 26 16:26:37 2000
@@ -29,6 +29,6 @@
 
 extern int packet_output(int, unsigned char *, int);
 extern int socket_phy_setup(char *);
-extern int socket_tap_setup(char *);
+extern int socket_tap_setup(char *, int *);
 
 #endif
diff -ruP uml-net-tools/um_eth_net_tap.c uml-net-tools.new/um_eth_net_tap.c
--- uml-net-tools/um_eth_net_tap.c	Mon Jul 24 20:42:47 2000
+++ uml-net-tools.new/um_eth_net_tap.c	Tue Sep 26 17:50:36 2000
@@ -5,19 +5,44 @@
 #include <fcntl.h> 
 #include <errno.h>
 #include "um_eth_net.h"
+#include "config.h"
 
-int socket_tap_setup(char *name) {
+#ifdef HAS_UNIVERSAL_TUNTAP
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if_tun.h>
+#endif
+
+int socket_tap_setup(char *name, int *headsize) {
   char nbuf[16];
   int retval = -EINVAL;
   int new_fd;
 
-  if(!strncmp(name,"tap",3)) {
-    sprintf(nbuf,"/dev/%s",name);
-    if((new_fd = open(nbuf,O_RDWR|O_NONBLOCK)) < 0) {
-      perror(nbuf);
-    } else {
-      retval = new_fd;
+  if(strncmp(name,"tap",3))
+    return retval;
+
+#ifdef HAS_UNIVERSAL_TUNTAP
+  if((new_fd = open("/dev/net/tun",O_RDWR)) >= 0) {
+    struct ifreq ifr;
+    memset(&ifr,0,sizeof(ifr));
+    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+    if(ioctl(new_fd,TUNSETIFF,(void *)&ifr) < 0) {
+      perror("/dev/net/tun");
+      close(new_fd);
+      return retval;
     }
+    *headsize = 0;
+    return new_fd;
+  }
+#endif
+
+  sprintf(nbuf,"/dev/%s",name);
+  if((new_fd = open(nbuf,O_RDWR|O_NONBLOCK)) < 0) {
+    perror(nbuf);
+  } else {
+    *headsize = 2;
+    return new_fd;
   }
 
   return retval;
diff -ruP uml-net-tools/um_eth_net_util.c uml-net-tools.new/um_eth_net_util.c
--- uml-net-tools/um_eth_net_util.c	Mon Jul 24 20:42:47 2000
+++ uml-net-tools.new/um_eth_net_util.c	Tue Sep 26 16:33:09 2000
@@ -109,9 +109,20 @@
       exit(-1);
     }
     for(in=1;in<argc;in+=2) {
-      if((new_fd = socket_tap_setup(argv[in])) > 0) {
+      int headsize;
+      if((new_fd = socket_tap_setup(argv[in], &headsize)) > 0) {
         fprintf(stderr,"TAP: %s\n",argv[in]);
-        type = SOCKET_TAP;
+        /* this is a dirty kludge to avoid a lot of changes: */
+        switch(headsize) {
+          case 0:
+            type = SOCKET_PHY; break;
+          case 2:
+            type = SOCKET_TAP; break;
+          default:
+            fprintf(stderr, "unknown header size before tap packet\n");
+            exit(EXIT_FAILURE);
+        }
+        /* end of kludge */
       } else if((new_fd = socket_phy_setup(argv[in])) > 0) {
         fprintf(stderr,"PHY: %s\n",argv[in]);
         type = SOCKET_PHY;


-- 
mar...@in...
software engineer                                       innominate AG
server appliances                                   networking people
tel: +49.30.308806-19  fax: -77                  http://innominate.de